Gear Oil revisited (HELP)

[wpurple]

For some unknown reason I was just thumbing through my owners manual and it states 75W140 Synthetic for front axle and 80W90 for rear unless 5.0 then synthetic.

I received 2 owners manuals with my truck back in 97.
When I picked up my truck the dealer couldn't find the manual so they took one out of another Explorer.

THAT manual said 80W90 for front axle, 80W90 for rear unless 5.0 OR 4.0 with 3.73 or 4.10 then 75W140

I went by the above and put 75W140 Motocraft Synthetic in rear and Mobil 1 80W90 in front.

Now I am all confused. Should I switch back to Mobil 1 80W90 in the rear and change the front to 75W140?
Will 75W140 do any harm in the rear, figure that the 5.0L has it factory filled? I have 3.73's not LS.
Here in CT it does get pretty cold in the winter and thought that 80W90 would be a better choice although I do tow a good size camper with the truck.

BTW Does the 5.0L use the same 8.8?

Me very much confused.

Kurt
97 Sport with mixed up oil

 

[taxx]

I am confused too. Everywhere I looked and everyone I talked to said something different. But I finally got a few dealerships to agree on 80w90 both front and rear. I am using synthetic and have not had any problems.

 

[AgExplorer]

Kurt,

As long as you're not doing any heavy off-roading or trailer towing, 75W-90 or 80W-90 will work fine in the front and rear diffs. I'd stick with a synthetic for their ability to run cooler.

 

[Robert]

Page 223 of my '97 Owner's Guide states that all front axles get 80W90 conventional gear oil. The rear differential may come with 80W90 or 75W140 synthetic or as Ford calls it "high performance synthetic rear axle fluid". All 5.0L Explorers or any Explorer equipped with a limited slip or 4.10 ratio get the 75W140. Everything else gets conventional gear oil.

 

[Jefe]

Originally posted by Robert
Page 223 of my '97 Owner's Guide states that all front axles get 80W90 conventional gear oil. The rear differential may come with 80W90 or 75W140 synthetic . . .

Thats what my 2000 manual says also.

 

[addkev]

You guys are right, my manual says 80W90 for the front, but my Haynes on page 1-23 say it is synthetic lubed for life. I guess we would want to follow the manual, huh?

Sorry for adding to the confusion.

 

[wpurple]

Looks like there are a few printings of the manual in 97, Guess Ford can't make up there mind.
I called 12 Ford Dealers around the country and the results are 50/50 between 80/90 and 75/140.

(Many say they go with the 80W90 dino as the customers freak at the price $17 a quart)

All agree that the 75W140 Synthetic will provide the best protection, and since it is synthetic you need not worry about it turning to tar in the winter.

The gear oil from Ford specifically for the front is 75W90,
it's a conventional dino. (I only asked one dealer about the front)

I am giong to leave the 75W140 in as I do tow and when I tow I leave it in mostly 4th so the rpm's are up.

Thanks,
Kurt

 

[briantf]

RedLine 75 140 = $8/qt

Not sure what Ford is selling, but the RedLine full synthetic in the correct weight is only $8/qt. Lot less than $17, that's for sure (have to buy 2, however, as it's a 1.5 qt job).

Regards,
Brian in CA

 

[94EBexplorer]

if your running synth's its always better to keep running them.... and not to change ...